基于光注入半导体激光器的宽带雷达信号产生及应用（特邀）

Wideband Radar Signal Generation and Application Based on An Optical Injected Semiconductor Laser

摘要:

由于具有动力学特性丰富、体积小和易集成等优点,基于半导体激光器的信号产生技术已成为高性能微波光子信号产生的优选方案之一。半导体激光器在合适的外光注入条件下能够工作在单周期振荡态,可突破本征弛豫振荡频率的限制,产生频率大范围可调的微波信号；进一步动态地控制注入参数,能够生成宽带可重构的微波调频信号,在雷达领域具有重要的应用前景。文章首先介绍了基于光注入半导体激光器的宽带微波信号生成机理并实验产生了大时宽带宽积的微波线性调频信号,其中心频率、带宽、时宽和工作频段均可灵活调谐；然后,构建了延时匹配光电反馈环路,提升了宽带微波调频信号的频谱纯度和梳齿信噪比等性能参数；最后,基于该高性能宽带微波调频信号发生器构建了微波光子雷达验证系统,分析了其在目标探测与成像方面的性能。

Abstract:

Due to the advantages of rich dynamics, small size and easy integration, semiconductor laser-based signal generation technology has become a potential candidate for high-performance microwave photonic signal generation. Under proper optical injection, semiconductor lasers can operate at the period-one (P1) oscillation state and break through the limitation of the intrinsic relaxation oscillation frequency to realize the generation of the widely tunable microwave signal. In addition, assisted by dynamical control of injection parameters, wideband reconfigurable microwave frequency-modulated (LFM) signals can be generated, which has important applications in radar systems. In this paper, the research progresses of the wideband radar signal generation and application based on an optically injected semiconductor laser were reviewed. Firstly, microwave LFM waveforms with large time-bandwidth products were successfully generated by exploring the controlled P1 dynamics of an optically injected semiconductor laser. The main operating parameters are adjustable, including the central frequency, bandwidth, frequency band, and temporal period. Secondly, a delay-matched optoelectronic feedback structure was introduced to greatly improve the spectral purity and phase coherence of the generated wideband radar waveform. Finally, by applying the generated wideband waveforms, a microwave photonic radar system was experimentally demonstrated, and its high-resolution target detection and imaging ability were verified.